ripping problems

i was wondering why some dvd's don't rip properly... ie. the fast and the furious...if i rip it as one file, i cannot fast forward or select any part of the movie using the progress bar, that automaticly jumps to the end. If i rip each vob's into separate files i don't get the correct audio file i selected or some of the files don't work.
I am using clad dvd to rip the dvd.